In the medicinal sector, in the pharmaceutical sector, in the cosmetic sector or in that of dietary supplements, extemporaneous-preparation products are known, i.e., products made up of the solution or of the mixing of at least two different substances, of which, e.g., one in the liquid state and the other in the powder state, which are kept separate the one from the other until the time of use.
For the packaging of extemporaneous-preparation products the use is known of bottles such as those described and illustrated in the patent document EP 0 963 325.
Such bottles are essentially made up of a tank which is closed on the bottom and which extends at the top in a neck, at the top of which is defined a dispensing mouth; inside the tank a first substance is contained, generally in the liquid state.
In the mouth of the tank is housed a container of a second substance which is made up of a hollow cylindrical body closed at the bottom by a breakable bottom and open at the top; the bottom of the container, as long as this remains intact, separates the second substance from the first.
Inside the container is inserted, sealed, a cutting member made up of a tubular body, the lower extremity of which is sectioned according to an oblique plane or which is bevel shaped and the upper extremity of which extends beyond the top opening of the container.
The cutting member is axially sliding with respect to the container between a non-interference configuration, wherein it is placed above the intact bottom of the container itself, and a cutting configuration, wherein, pushed towards the bottom of the container, it cuts this along the perimeter edge putting the container, thus opened, into communication with the tank.
The known bottles, furthermore, have a cover cap which is associated with the neck of the tank by means of a threaded coupling; the lower edge of the cap is temporarily secured, along a breakage line, to a seal ring secured to the neck of the tank and having a weakened axial line in correspondence to which it opens.
Finally, inside the cap, an annular relief is defined which, after the cap has been screwed onto the neck of the tank, couples with the upper edge of the container, which is elastically deformable in a centripetal direction, to form a single body piece with this.
At the time of using the product, the cap is screwed onto the neck of the tank to break the seal ring which detaches from this and opens. The screwing up of the cap causes the sliding of the cutting member inside the container until the bottom of the latter is cut; the second substance is then poured from the container into the tank, inside which it mixes with the first to form the product. To dispense the product thus formed, the cap has simply to be unscrewed to also remove, integral with this, the container and the cutting member opening the dispensing mouth of the tank.
These bottles of known type are not without drawbacks, among which should be recalled the fact that, though keeping the two substances separate until the preparation of the product, they do not permit completely isolating the one with respect to the other.
In particular, the vapours coming from the outside environment and/or those released by the liquid substance in the tank permeate, in part, inside the container where a powdery, often hygroscopic substance is generally present. Before the preparation of the product, when the two substances are still separated, the powdery substance absorbs the vapours released by the liquid substance impregnating itself with these and becoming dense in agglomerates. When, at the time of preparing the product, the container is opened and placed in communication with the tank, the agglomerates which have formed tend to remain inside the container and, even when they have been poured into the tank, they have difficulty in dissolving and dispersing themselves completely in the liquid substance.
The composition of the product thus formed does not correspond to that provided for it; in the event of the product being a drug or a medicinal, this causes an indeterminable alteration of the contents of its active ingredients and of the dosage established for it and, therefore, a disadvantageous modification of the therapy studied for a patient.
Such drawback is accentuated by the fact that the containers of known bottles are generally made of polymer materials which have a certain degree of permeability to vapours.
Permeability to vapours is further accentuated in correspondence to the bottom of the container which, being of a breakable type, generally has a reduced thickness and/or is fastened to the member of the container along weakened lines of even more reduced thickness.
To overcome such drawbacks at least in part, bottles are known like those illustrated in the documents EP 1 186 548 and EP 1 858 774, wherein the container containing the second substance defines an insulating interspace to hinder the transit of the vapours released by the liquid substance.
In any case, these bottles are not exempt from drawbacks either.
Recent studies have shown that the presence of an insulating interspace can only delay the diffusion of the vapours released by the liquid substance and, therefore, not prevent their absorption by the powdery substance and the formation of inconvenient agglomerates.